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Diffstat (limited to 'compiler-rt/lib/arm/comparesf2.S')
| -rw-r--r-- | compiler-rt/lib/arm/comparesf2.S | 148 |
1 files changed, 0 insertions, 148 deletions
diff --git a/compiler-rt/lib/arm/comparesf2.S b/compiler-rt/lib/arm/comparesf2.S deleted file mode 100644 index ad1b10a7fd3..00000000000 --- a/compiler-rt/lib/arm/comparesf2.S +++ /dev/null @@ -1,148 +0,0 @@ -//===-- comparesf2.S - Implement single-precision soft-float comparisons --===// -// -// The LLVM Compiler Infrastructure -// -// This file is dual licensed under the MIT and the University of Illinois Open -// Source Licenses. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file implements the following soft-fp_t comparison routines: -// -// __eqsf2 __gesf2 __unordsf2 -// __lesf2 __gtsf2 -// __ltsf2 -// __nesf2 -// -// The semantics of the routines grouped in each column are identical, so there -// is a single implementation for each, with multiple names. -// -// The routines behave as follows: -// -// __lesf2(a,b) returns -1 if a < b -// 0 if a == b -// 1 if a > b -// 1 if either a or b is NaN -// -// __gesf2(a,b) returns -1 if a < b -// 0 if a == b -// 1 if a > b -// -1 if either a or b is NaN -// -// __unordsf2(a,b) returns 0 if both a and b are numbers -// 1 if either a or b is NaN -// -// Note that __lesf2( ) and __gesf2( ) are identical except in their handling of -// NaN values. -// -//===----------------------------------------------------------------------===// - -#include "../assembly.h" -.syntax unified - -.align 2 -DEFINE_COMPILERRT_FUNCTION(__eqsf2) - // Make copies of a and b with the sign bit shifted off the top. These will - // be used to detect zeros and NaNs. - mov r2, r0, lsl #1 - mov r3, r1, lsl #1 - - // We do the comparison in three stages (ignoring NaN values for the time - // being). First, we orr the absolute values of a and b; this sets the Z - // flag if both a and b are zero (of either sign). The shift of r3 doesn't - // effect this at all, but it *does* make sure that the C flag is clear for - // the subsequent operations. - orrs r12, r2, r3, lsr #1 - - // Next, we check if a and b have the same or different signs. If they have - // opposite signs, this eor will set the N flag. - it ne - eorsne r12, r0, r1 - - // If a and b are equal (either both zeros or bit identical; again, we're - // ignoring NaNs for now), this subtract will zero out r0. If they have the - // same sign, the flags are updated as they would be for a comparison of the - // absolute values of a and b. - it pl - subspl r0, r2, r3 - - // If a is smaller in magnitude than b and both have the same sign, place - // the negation of the sign of b in r0. Thus, if both are negative and - // a > b, this sets r0 to 0; if both are positive and a < b, this sets - // r0 to -1. - // - // This is also done if a and b have opposite signs and are not both zero, - // because in that case the subtract was not performed and the C flag is - // still clear from the shift argument in orrs; if a is positive and b - // negative, this places 0 in r0; if a is negative and b positive, -1 is - // placed in r0. - it lo - mvnlo r0, r1, asr #31 - - // If a is greater in magnitude than b and both have the same sign, place - // the sign of b in r0. Thus, if both are negative and a < b, -1 is placed - // in r0, which is the desired result. Conversely, if both are positive - // and a > b, zero is placed in r0. - it hi - movhi r0, r1, asr #31 - - // If you've been keeping track, at this point r0 contains -1 if a < b and - // 0 if a >= b. All that remains to be done is to set it to 1 if a > b. - // If a == b, then the Z flag is set, so we can get the correct final value - // into r0 by simply or'ing with 1 if Z is clear. - it ne - orrne r0, r0, #1 - - // Finally, we need to deal with NaNs. If either argument is NaN, replace - // the value in r0 with 1. - cmp r2, #0xff000000 - ite ls - cmpls r3, #0xff000000 - movhi r0, #1 - JMP(lr) -END_COMPILERRT_FUNCTION(__eqsf2) -DEFINE_COMPILERRT_FUNCTION_ALIAS(__lesf2, __eqsf2) -DEFINE_COMPILERRT_FUNCTION_ALIAS(__ltsf2, __eqsf2) -DEFINE_COMPILERRT_FUNCTION_ALIAS(__nesf2, __eqsf2) - -.align 2 -DEFINE_COMPILERRT_FUNCTION(__gtsf2) - // Identical to the preceeding except in that we return -1 for NaN values. - // Given that the two paths share so much code, one might be tempted to - // unify them; however, the extra code needed to do so makes the code size - // to performance tradeoff very hard to justify for such small functions. - mov r2, r0, lsl #1 - mov r3, r1, lsl #1 - orrs r12, r2, r3, lsr #1 - it ne - eorsne r12, r0, r1 - it pl - subspl r0, r2, r3 - it lo - mvnlo r0, r1, asr #31 - it hi - movhi r0, r1, asr #31 - it ne - orrne r0, r0, #1 - cmp r2, #0xff000000 - ite ls - cmpls r3, #0xff000000 - movhi r0, #-1 - JMP(lr) -END_COMPILERRT_FUNCTION(__gtsf2) -DEFINE_COMPILERRT_FUNCTION_ALIAS(__gesf2, __gtsf2) - -.align 2 -DEFINE_COMPILERRT_FUNCTION(__unordsf2) - // Return 1 for NaN values, 0 otherwise. - mov r2, r0, lsl #1 - mov r3, r1, lsl #1 - mov r0, #0 - cmp r2, #0xff000000 - ite ls - cmpls r3, #0xff000000 - movhi r0, #1 - JMP(lr) -END_COMPILERRT_FUNCTION(__unordsf2) - -DEFINE_AEABI_FUNCTION_ALIAS(__aeabi_fcmpun, __unordsf2) |
